Web development in android

well I got to develop an android app that connects to a specific website each time the site is updated by the admin and I want a code that does this.(actually we need to send news to users that have installed the app) for example the link is mysite.com/news.php so the app connects to this address and downloads the news and save them...I just don't know where to start.please if anyone can show me how. if there is another way to send the news to a specific number of users tell me too...thanks